On the identity of Sundathelphusa philippina (von Martens, 1868) (Decapoda: Brachyura: Gecarcinucidae) from the Philippines, with descriptions of two new species.

The taxonomy of the Sundathelphusa philippina (von Martens, 1868) species group (Brachyura; Gecarcinucidae) from the Philippines is revised, and two new species are described. Sundathelphusa philippina sensu stricto is here restricted to the Bicol Peninsula of southern Luzon, and to the islands of Samar and Leyte. It is one of the largest freshwater crabs in the archipelago, reaching carapace widths of more than 53 mm. Sundathelphusa cebu sp. nov. from Cebu Island is superficially similar to S. philippina in morphology but can be separated by a suite of carapace characters. Sundathelphusa quirino sp. nov. from northern Luzon is the most distinct of the three taxa, with a distinctly more swollen carapace, relatively wider male pleon and a straighter male first gonopod. Sundathelphusa spelaeophila Stasolla, Abbarchi Innocenti, 2015, is also shown to be a junior synonym of S. philippina sensu stricto.